Method of separation of lanolin from crude wool-grease and the like



UNITED STA ES PATENT OFFICE.

FLOYD J; METZGER, on NEW YORK, N. Y.

METHOD SEPARATION OF LANOLINFROM CRUDE WOOL GBEASE AND THE LIKE.

Specification of Letters Patent.

No Drawing. Application filed June 7, 1916, Serial No. 102,198. Renewed June 16, 1919. Serial No.

To all whom it may concern:

Be it known that I, FLOYD J. Mnrzonn, a citizen of the United States of America, and a resident of the borough of Manhattan, city, county, and State of New York, have invented certain new and useful Improvements in Methods of Separation of Lanolin from Crude Wool-Grease and the like, of which the following is a specification.

This invention relates to a method of separating crude lanolin from the greases recovered from the wash liquors in which wool is scoured, preparatory to its use in the various textile industries.

Crude wool grease, as it is recovered from wool wash liquors, contains among other substances a mixture of lanolin with free fatty acids and saponifiable matter. In the preparation of commercial lanolin it is necessary to separate and remove more or less of the saponifiable matter and substantially all of the free fatty acid. Lanolin forms, in alkaline soap solutions, a permanent emulsion from which it is separated with the greatest difficulty. Numerous methods of separating crude lanolin from these emulsions have been suggested, such as by high centrifugal force or by the action of solvents after the soluble soaps have been converted to insoluble soaps or by a form of flotation in which air is blown through the emulsion, etc.

The object of my invention is to provide a simple and efficient method for the separation of crude lanolin from wool grease. By the practice of this process I am able to obtain from crude wool grease, in a single operation, a separation of the major portion of the lanolin content, and at the same time obtain the other greases in an easily recoverable form.

I have discovered that the emulsification of the lanolin in the soap solution produced by the action of alkali on the fatty acids and saponifiable matter in crude wool grease may be prevented by the copresence, in the alkali treating solution, of a suitable concentration of a soluble salt. By suitably adjustin the conditions as more fully describe hereinafter, I am able to effect a simple separation of the two principal con-.

stituents of wool grease in such a form as to render their recovery and utilization a simple and-efiective operation. The sapomfied and soapy matter is not precipitated, but stays 1n solution or suspension in the treating liquor, when the conditions of my effected.

The crude lanolin produced by my method may be subjected to a further treatment for bleaching and deodorizing, in order to produce a high grade commercial product for use in pharmaceutical and other industrial applications. The residual greases and oils may be at the same time recovered and converted, by suitable treatment, into materials for use in the various arts in which such fats, and especially those containing a small quantity of lanolin are desired.

In the practice of my method of treat ment a. quantity of crude wool grease is treated with a treating solution containing the proper proportions of an alkali and a soluble salt, sufficient salt being present to separate out the lanolin without salting out the soap. I prefer to use caustic soda as the alkali and a soluble salt of the alkali group, such as a sodium, potassium or ammonium salt, as the salt. It is highly desirable, if not essential, that the alkali and the salt be present together in the treating solution when the latter is applied to the crude wool grease because, if the alkali is first applied, followed by the salt, an emulsion is formed on which the salt has no sufficient separating effect.

The mixture thus produced is boiled and agitated for a considerable time, as a result of which treatment the unsaponifiable lanolin collects and floats on the surface, while the saponifiable greases and other constituents of the crude wool grease remain in solution or suspension in the treating mixture. The batch is then allowed to stand without further agitation so that the crude lanolin may collect on the surface and be removed by any suitable means.

In the practice of my invention I have found the best results to be obtained when I have added to the crude wool grease containing a determined amount of free fatty acid, a. sufficient amount of treating solution to give an amount of alkali about one and onehalf times theory based on the amount of fatty acid present, said treating solution conpercentages taining as well about five per cent. by weight of the soluble salt used; Both of these percenta es may be varied'within limits so long as su 'cient salt is present to separate out the lanolin and not salt out the soap and alkali enough is present suflicient to saponify substantially all of the free fatty acid present and more or less of the remaining saponifiable matter without formingan emulsion of the lanolin. Approximately one and onehalf times theory of alkali based on the amount of fatty acid present and from four to six per cent. by welght of soluble salt answers these requirements. The percentage of free fatty acid present in the crude wool grease may first be ascertained and then sufficient treating solution added to glve the of alkali and soluble salt stated. The treating solution may be made up and kept in tanks ready for use, a sufficient amount being used in each instance to satisfy the requirements of the particular grease undergoing treatment.

As a specified illustration ofone way of practising the method used in carrying out my process, I refer to the following example.

100 pounds of crude wool grease conta1ning 18 per cent. of free fatty ac ds is melted by any suitable means and to this is added 120 gallons of an aqueous solution containing l pounds of caustic soda (about 0.4 per cent. by weight) and 50 pounds of sodium chlorid (about 5 per cent. by weight).- The mixture is boiled and agitated by the introduction of live steam for two to three hours, after which the steam is shut off and the batch is allowed to stand six hours or more. The crude lanolin which rises to the surface is removed mechanically, or the liquid may be drawn off from the bottom, allowing the crude lanolin to remain in the vessel. This crude lanolin is washed with water after which it is ready to be transferred to the crude lanolin storage tanks.

The treating solution from the above operation, after the lanolin has been separated .out. may be acidifiedwith 15 pounds of sul-' furic acid, or its equivalent, and heated and pounds of fatty materials, substantially one half of the original weight, in the form, of crude, neutral lanolin and half in the form of other fatty materials.

\Vhile the particular sample of crude wool grease used in the above test yielded approximately 50 per cent. of crude lanolin, it

is obvious that the amount recovered Will bear a direct relation to the composition of the original grease.

In the practice of my invention, as outlined above in detail, I do not limit myself to the use of common salt (sodium chlorid), but may use in its place other soluble salts of the alkali group, such as sodium-nitrate, sodium sulfate and the like, as well as the oofresponding potassium and ammonium sa ts.

Furthermore, I do not limit myself to the exact proportions of alkali or salt given in the above specific example, since these proportions are variable and dependent upon the quantity of saponifiable matter contained in the crude wool grease. And where I in the claims I refer to a solution I mean to include a suspension as well.

I claim.

1. A method of se aratin lanolin from crude wool grease and the li e consisting in subjecting the crude wool grease to the action of a treating solution containing both an alkali and a soluble salt of the alkali group, the alkali being presnt in suflicient proportion to substantially completely saponify all of the free fatty acid present.

2. A method of separating lanolin from crude WOOl grease and the like consisting in subjecting the crude wool grease to the action of a treating solution containing both caustic soda and a soluble salt of the alkali oup, the caustic soda being present in sufcient proportion to substantially completely saponify all of the free fatty acid present.

3. A method of separating lanolin from crude wool grease and the like consisting in subjecting the crude wool grease to the ac- 105 tion of a treating solution containing both an alkali and sodium chlorid, the alkali being present in sufficient proportion tosubstantially completely saponify all of the free fatty acid present. a

4. A method of separating lanolin from crude wool rease and the like consisting in subjecting t e' crude wool grease to the action of a treating solution containing both caustic soda and sodium chlorid, the caustic 116 soda being present in sufiicient proportion to substantially completely saponify all of the free fatty acid present.

5. A method of se arating lanolin from crude wool grease an' the like consisting in 120 subjecting the crude wool grease to the action of a treating solution containing approximately one and half times the theoretical amount of alkali based on the free fatty acid in the grease and from approximately tion of a treating solution containing ap- In testimony whereof I have signed this proximately four tenths of one per cent. by specification in the presence of two subscrib- Weight of caustic soda and approximately ing witnesses.

five per cent. of sodium chlorid in sufiicient FLOYD J. METZGER. amount to give substantially one and a half Witnesses:

times the theoretical amount of alkali based HELEN RYAN,

0n the free fatty acid present in the grease. CHARLES F. CLAAR. 

